It just doesn't strike me as obvious that reducing the major radius by a few meters would have such a huge impact on cost/timelines.
[0] https://library.psfc.mit.edu/catalog/online_pubs/iap/iap2016...
This quote from the presentation summarizes it well:
“The more money that's involved, the less risk people want to take. The less risk people want to take, the more they put into their designs, to make sure their subsystem is super-reliable. The more things they put in, the more expensive the project gets. The more expensive it gets, the more instruments the scientists want to add, because the cost is getting so high that they're afraid there won't be another opportunity later on- they figure this is the last train out of town. So little by little, the spacecraft becomes gilded. And you have these bad dreams about a spacecraft so bulky and so heavy it won't get off the ground- never mind the overblown cost.”
“That boils down to the higher the cost, the more you want to protect your investment, so the more money you put into lowering your risk. It becomes a vicious cycle.” - Rob Manning, Chief spacecraft engineer, JPL
>In 1992, Dan Goldin became the NASA Administrator. Goldin believed in a philosophy of Faster… better… cheaper—i.e., he thought NASA could do more with less. Hence, Goldin did not support the idea of having large EOS platforms in space and in fact once referred to them as “Battlestar Galactica.” He believed smaller, less expensive missions that could be built more quickly were the way to go and supported development of new programs that actually diverted funds from EOS.
[1] https://eospso.nasa.gov/sites/default/files/eo_pdfs/Perspect...
In any case, this exact question was asked here, and the top-rated response indicates that it's unlikely that the design requirement was ever meant to refer to grabbing an uncooperative payload:
https://space.stackexchange.com/questions/41741/was-the-spac...
SpaceX's advancement is impressive, but if NASA had never happened, I doubt SpaceX would even exist today.
It's all completely bespoke scientific equipment hand made for this project only. The cryostat will be the largest stainless steel vacuum vessel ever made-- all welded by hand.
After welding, a substantial number of in-vessel components have to be installed by threading them through access ports, which is also quite a task: https://www.youtube.com/watch?v=pt70mO2nQac
That said building the first is a lot harder than scaling it up.
(That's right. ITER, which will cost more than $65 billion and take decades to build, can't run continuously!)
When you have no turbine or any other means to extract power from a heat source, none gets extracted. Do you need a source for that?
>It just doesn't strike me as obvious that reducing the major radius by a few meters would have such a huge impact on cost/timelines.
It would, easily. Past a certain size, production costs rise exponentially and require one-off tech.
Or is it massive like the tokamak is a 6 meter engine to a 100 km collider? Like there's a ton of other stuff being built in a massive structure?
1. As budget constraints tighten, the number of man-hours spent wrestling with bean counters (and/or waiting around with nothing to do until the bean counter wrestling completes) increases exponentially.
2. "Cheap solutions" often end up being unfit for purpose, and have to be reworked later at great expense.
3. Budget overruns lead to time overruns which lead to more budget overruns, ad infinitum.
So there’s very little incentive to constrain costs.
The alternative would be that management cannot be judged on its results.
Some bridges, invariably urban, go massively over budget and schedule. Urban tunnels, routinely. Military procurement, routinely. Are people who manage those systematically dumber than the rest? Or do they have different measures of success?
What is common to those apparent failures is that they serve as a reliable, legal, long-term conduit from public funds to a multitude of private pockets. F-35 can never be cancelled, no matter what, because it has subcontractors in 48 states. The F-35 is a massive success to its backers: it secured monumental patronage. That it can actually take off and land, too, is a miracle.
The statement is that a blue-sky project such as a fusion system is easily recognized by people on the lookout for sources of unlimited money with no strings attached. When they get control of the project, the bulk of the money will not end up spent on the extremely difficult problems entailed. If the problems are as difficult as expected, handing the money over to people who benefit by not solving them will reliably fail to solve them.
We know with absolute certainty, already, that there is no "holy grail of energy production" at the end of it. The most favorable imaginable result is a system much more expensive to operate than a fission plant that produces no more power.
This is already demonstrated by your own examples provided, just at a smaller scale.
If there were ever such a project to push against the capacity of our ability to do truly enormous, complex engineering, I’d say a massive, cutting-edge fusion reactor is as good a candidate as one could propose.
Moreover, the economic and educational stimulus these projects provide cannot be ignored when accounting for the indirect, long-tail returns this project, and those similar, provide.
Put another way: ostensibly, achieving net energy gain from fusion is the end of our near-term (energy) needs, conveniently breezing over the evolution and refinements of any system, as well as delivery and storage, but these are paths that are comparatively well mapped out. It then follows that, short of catastrophic losses prior to succeeding (which while not a given per se, seems more a function of time than of ability outright), any reasonable cost is worthwhile. Reasonable, in this context, meaning one that doesn’t bankrupt, or otherwise severely impact the participants in a negative fashion. Given the scale of these budgets vs. that of social welfare programs, military spending, etc. I don’t see that as an issue worth being concerned over. One can know the budget has been exceeded, without that also bringing down the house.
Ultimately, to an extent you’re asserting a false dichotomy. It can be true that there’s continued, substantial progress towards the stated goals of these projects, even if the budgets, horizons, and timelines aren’t to your taste. It can also be true that there’s waste, inefficiencies, and even (both legalised and otherwise) corruption. One does not preclude the other.
We know already that if the project achieves all of its projected goals, the result will be much more expensive than fission. We know already that if any power is ever generated, at any price, it can come no sooner than decades in the future.
Being delayed imposes costs on downstream work, which must now be ready but in some kind of holding pattern, which imposes costs on work downstream of that work.
So a large part of throwing "Manhattan project" / excess funding (and the potential savings by just funding it that way from the start) is avoiding these delays, to the extent possible.
It costs +$200,000 to tackle some challenge in a critical piece? Sometimes it's cheaper just to pay.
ITER is likely bigger in terms of volume of concrete or actual footprint.
[0]https://ieeexplore.ieee.org/document/1018583 [1]https://www.iter.org/mach/Magnets
We see it lately in the numerous military procurements (particularly the F-35 program), in NASA's SLS rocket, in California's bullet train to nowhere, and urban tunnels such as New York's 2nd Avenue subway extension. It is why nuke plants are invariably so expensive and late.
In a word, corruption.
Lately, this corruption has been arranged to be wholly legal, so there is no possibility of prosecution. The majority of the money spent is funneled into myriad private pockets without moving the project toward completion. Nobody involved, at the monetary level, has any desire for it ever to be completed, because that is when the gravy train stops.
Fusion projects represent the worst case of this phenomenon. Nobody knows what it should cost, and nobody in control of spending wants it over with, ever.
The chance that anything of any practical use could come out at the end was openly foreclosed before it ever started: it was never promised to produce any electrical power, and no turbines, or space for any, appear in any site plan.
Any sort of practically useful Tokamak plant would need to be overwhelmingly bigger and more expensive than ITER, and could never come anywhere near producing commercially competitive power, so the project is a known dead end, to be milked until it is finally cancelled in shame.
What is tragic is that each euro diverted to this boondoggle brings climate disaster terrifyingly closer.
The sole fact that such a scientific undertaking can be done internationally, over decades, is a great thing considering the global problems we face.
Yes, ITER doesn't follow the USA economic ideology of "much", "cheap", and "now", but the world doesn't consist only of the USA and not everything works well with that ideology.
ITER is not a PV or battery factory. It is more like the ISS.
I have no doubt that plasma fluid physicists will learn a great deal from trying to get ITER lit up. Just handed the money, they could have learned a thousand times more, and maybe even achieved practical D/H-3 fusion propulsion for spacecraft. But that will not happen at ITER.
And for comparison, look what the ISS has brought us commercially: We have a fully commercial manned spaceflight planned for next week. That is a massive achievement without even considering all the scientific work on the station.
All of the "scientific work on" ISS is done with crew literally pushing an "on" button on each bit of automated equipment running it. Experiments are forbidden to involve more interaction, and also forbidden to operate without that "on" button, so the crew has something, anything to do.
Commercial manned spaceflight could better have been worked without ISS. ISS's role was nothing more than a place to take them. Plus, a huge money sink on its own. It will soon fall out of the sky, and with any luck not hurt anybody where it crashes down.
Why is this relevant?
Akin's law of spacecraft #29 "To get an accurate estimate of final program requirements, multiply the initial time estimates by pi, and slide the decimal point on the cost estimates one place to the right."
A 6m device occupies 666 (say) --216 m^3
a 10m device occupies 10 10 6 (say) -- 600 m^3
The scale of volume means that you have to build a much bigger facility to put it in (in order for the electronics to be kept dry and for people to be able to get around it to keep birds off it and things.
But worse - the weight. Concrete is 2400kg m ^3 so the small device might weigh 518 tonnes, but the bigger device is 1440 tonnes, so moving parts of it round becomes 3 * harder, the floors have to be 3* stronger, the supply chain has to be 3* better.
And then time - 3* scale, 3* engineering challenge -> many times more time to deliver, many more $$$ -> risk -> planning -> admin... the less capital at risk the less it's worth spending on avoiding the risk.. the less the overhead of the project is.
FWIW ITER is a science experiment - it's designed to find out more about fusion and that data will be very valuable for future reactor designs.